JPH04185689A - Ultraviolet absorber for acrylic fiber and method for light stabilization of the acrylic fiber - Google Patents

Abstract

PURPOSE:To obtain the title absorber which is excellent in the compatability with an acrylic fiber and causes less leaching into a coagulating bath in wet spinning by using a copolymer of a compound which contains a prescribed amount of a specific benzophenone compound and a vinyl compound which is copolymerizable therewith. CONSTITUTION:The title absorber comprises a copolymer of a compound which contains 20 to 80wt.% benzophenone compound represented by the formula (wherein R represents hydrogen or CH3; and X represents O, OCH2CH2O or OCH2C(OH)HCH2O) and a vinyl compound copolymerizable therewith, such as methyl methacrylate.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses copolymerization of 2-hydroxybenzophenones having a polymerizable vinyl group and a vinyl compound as a polymer type ultraviolet absorber. This paper concerns the light stabilization of acrylic fibers, which have had problems in terms of compatibility, heat resistance, and production systems such as wet spinning.

Resin moldings and acrylic fibers used outdoors are exposed to sunlight on a daily basis, and exposed to fluorescent light indoors. Sunlight and fluorescent light contain ultraviolet rays of 200 to 400 nm that are harmful to polymer materials.
This ultraviolet light excites the functional groups in the polymer and the remaining polymerization catalyst, resulting in a photodegradation reaction that degrades the polymer and discolors the dye added to the polymer.

In order to protect polymers, dyes, etc. from such harmful light, ultraviolet absorbers are usually added. Ultraviolet absorbers protect macromolecules from photodegradation reactions by absorbing all or most of the light in the harmful region, converting the energy into harmless energy such as non-radiative transitions, and emitting it. It also prevents dyes from fading.

Because of their purpose, ultraviolet absorbers can volatilize, elute, or decompose during molding of polymers and fibers, or dyeing fibers, or bleed out and scatter on the product surface after it is made into a product. must not.

Particularly for wet-spun fibers, polymers such as dimethylformamide (DMF), dimethylacetamide (DMA), etc.
C), dimethyl sulfoxide CDMS○) and other solvents are spun in a coagulation bath of acetone, water/methanol, etc., so the ultraviolet absorber must not be eluted into the coagulation bath at this time. Currently, there are no ultraviolet absorbers currently available on the market that satisfy the above-mentioned problems.

In addition, textile products are usually subjected to an operation called dyeing,
At this time, if the ultraviolet absorber dissolves into the dyeing solution, problems such as a decrease in light resistance arise. Therefore, the photostability of wet-spun acrylic fibers depends on the coagulation bath of ultraviolet absorber,
It largely depends on the solubility in the dye solution or the compatibility with the fiber polymer.

Conventional ultraviolet absorbers include 2-hydroxybenzophenones such as 2,4-dihydroxybenzophenone, 2.2', 4.4'-tetrahydroxybenzophenone, and 2-hydroxy-4-octoxybenzophenone;
2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3', 5
Although 2-hydroxyphenylbenzotriazoles such as '-dibutylphenyl)-5-chlorobenzotriazole are widely used, they do not satisfy the above requirements.

Conventional UV absorbers dissolve in the coagulating liquid during wet spinning of acrylic fibers, so most of the UV absorbers are eluted into the coagulating liquid during spinning, resulting in problems such as the added UV absorbers not being able to be used effectively. There is a point. In addition, conventional UV absorbers are generally low-molecular compounds with a molecular weight of about 200 to 400, so they have poor compatibility with acrylic fibers, lack heat resistance, and tend to elute from acrylic fibers or decompose during dyeing or washing. However, it was not possible to impart long-term photostability to acrylic fibers.

In particular, acrylic fibers containing halogen-based copolymer components such as vinyl chloride and vinylidene chloride require a larger amount of ultraviolet absorber than other fibers to increase their light resistance. Currently, there is no method for imparting effective photostability to such acrylic fibers because they have poor compatibility with conventional ultraviolet absorbers and the ultraviolet absorbers added during wet spinning dissolve.

In addition, Honro Ganto previously synthesized the copolymer of the present invention,
It was proposed that this copolymer is useful as an ultraviolet absorber and can be widely applied as an additive type polymeric ultraviolet absorber or an ultraviolet absorbing copolymer (Japanese Patent Application Laid-open No. 180909/1999).
Publication No.).

However, this publication does not suggest at all that the copolymer of the present invention is used to photostabilize acrylic fibers.

The present invention provides a polymer type ultraviolet absorber that has good compatibility with acrylic fibers and does not elute into a coagulation solution even during wet spinning of acrylic fibers, and a method for photostabilizing acrylic fibers. be.

Five balls! The present invention provides a copolymer of a benzophenone compound represented by the following general formula (r) and a vinyl compound copolymerizable with the compound, wherein the benzophenone compound is
The copolymer containing 80% by weight is used as an ultraviolet absorber to light stabilize the acrylic fiber.

(In the formula, R: hydrogen or methyl group
HCH,O-) H Hereinafter, the present invention will be explained in more detail.

Specific examples of the 2-hydroxybenzophenone monomer of the general formula (1) include 2-hydroxy-4-methacryloxybenzophenone, 2-hydroxy-4-(2
-methacryloxy)ethoxybenzophenone, 2-hydroxy-4-(2-hydroxy-3-methacryloxy)propoxybenzophenone, and the like.

As the other copolymerization component constituting the copolymer of the present invention, a vinyl compound copolymerizable with the above benzophenone monomer is used, including alkyl esters of acrylic acid, alkyl esters of methacrylic acid, alkyl vinyl ethers, and alkyl Vinyl esters and the like are preferably used.

The alkyl chain length in the alkyl ester of acrylic acid, the alkyl ester of metal grillic acid, the alkyl vinyl alcohol, and the carbon number of the carboxylic acid residue in the alkyl vinyl ester are preferably 1 to 8, more preferably 1 to 4. be. When the number of carbon atoms is 9 or more, the softening temperature of the copolymer decreases and the compatibility with acrylic fibers decreases, which is not preferable.

Alkyl esters of acrylic acid include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; examples of alkyl esters of methacrylic acid include methyl methacrylate, ethyl methacrylate, and methacrylate. Examples include propyl and butyl methacrylate.

Examples of the alkyl vinyl ether include methyl vinyl ether, ethyl vinyl ether, and butyl vinyl ether.

Examples of alkyl vinyl esters include vinyl formate, vinyl acetate, vinyl acrylate, vinyl butyrate, vinyl crotonate, and the like.

The homopolymer of the 2-hydroxybenzophenone monomer represented by the general formula (1,) has poor compatibility with acrylic fibers, and bleeds out from the acrylic fibers over time, gradually becoming less effective.

On the other hand, copolymerizing the 2-hydroxybenzophenone monomer represented by general formula (1) with a vinyl compound improves compatibility with acrylic fibers, and even when added as an ultraviolet absorber, the original acrylic It has been found that this has no adverse effect on the physical properties of the fiber.

For this purpose, the 2-hydroxybenzophenone monomer represented by general formula (I) must be present in the copolymerization component at 20 to 8
It is necessary to contain 0% by weight, preferably 2% by weight.
It is 0 to 70% by weight. When the content of 2-hydroxybenzophenone represented by general formula (I) exceeds 80% by weight, the properties of the 2- and droxybenzophenone skeleton become strong, resulting in a decrease in compatibility with acrylic fibers. on the other hand,
If it is less than 20% by weight, the effect of improving photostability will be reduced.

Further, the copolymer of the 2-hydroxybenzophenone monomer and the vinyl compound of the present invention has a weight average molecular weight of 5.
It is preferably from 000 to 100,000, more preferably from 15,000 to 70,000. If the molecular weight becomes too large, the copolymer will not dissolve in the solvent during wet spinning, so not only will the polymeric UV absorber of the present invention not be able to be added to acrylic fibers, but the compatibility with acrylic fibers will decrease. Also, the molecular weight is too small.

The copolymer dissolves into the coagulation liquid during wet spinning.

It becomes ineffective and tends to bleed out from the acrylic fiber.

A copolymer of a 2-hydroxybenzophenone monomer represented by general formula (1) and a vinyl compound can be produced by solution polymerization,
It can be easily polymerized using common polymerization operations such as suspension polymerization and emulsion polymerization.

In order to photostabilize acrylic fibers using the polymer type ultraviolet absorber of the present invention, the copolymer of the present invention is mixed with the acrylic polymer in DMF.

It may be dissolved in a solvent such as DMAc or DMS○ to obtain a spinning dope, and this may be spun in a coagulating solution.

The ultraviolet absorber of the present invention does not dissolve into the coagulation solution, but remains and is incorporated into the spun acrylic fibers to exert a photostabilizing effect. In addition, the ultraviolet absorber of the present invention has good compatibility with acrylic polymers, especially acrylic polymers (copolymers) containing halogen monomers such as vinyl chloride and vinylidene chloride as copolymer components, and these acrylic polymers The photostability of the fiber obtained by spinning can be improved.

The ultraviolet absorber of the present invention is suitably added in a proportion of 0.01 to 10% by weight based on the acrylic polymer.

It is difficult to obtain the target photostability when adding only a drop of 0 or 1% by weight of O, and if the amount added is more than 10% by weight, the physical properties of the acrylic fibers will be different.

The polymer type ultraviolet absorber of the present invention can be used together with other additives, such as other light stabilizers, antioxidants, pigments, and dyes, if necessary.

According to the present invention, the photostability of acrylic fibers can be improved by using a copolymer of a specific hydroxybenzophenone compound and a vinyl compound as an ultraviolet absorber for acrylic fibers. . This copolymer has good compatibility with acrylic fibers, has little elution into the coagulation bath during wet spinning, and is suitable for acrylic fibers, especially acrylic fibers containing halogen monomers, which have been considered difficult to photostabilize. The photostability of fibers can also be improved.

Sue JLJL Example 1: Synthesis of copolymer of 2-hydroxy-4-methacryloxybenzophenone and methyl methacrylate In a 1Ω separable flask equipped with a Dimroth, dropping funnel, thermometer, nitrogen introduction tube, and stirring device, 2 -Hydroxy-4-methacryloxybenzophenone 111.5g,
Add 445 g of methyl methacrylate, 0.4 g of lauryl metalcaptan, and 560 g of ethyl acetate, and raise the temperature to 50° C. while blowing nitrogen through the nitrogen introduction tube. Then azobisisobutyronitrile dissolved in a small amount of ethyl acetate (
1.66 g (hereinafter abbreviated as rAIBNJ) was dropped in about 20 minutes, and after the dropwise addition was completed, the temperature was further raised to 70° C., and the reaction was carried out in a nitrogen atmosphere for about 8 hours. In addition, the stirring speed is 1100r
p. After the reaction was completed, it was cooled to room temperature, and the contents were poured into about 5 times the amount of methanol to precipitate a copolymer.

This precipitate was separated by suction filtration, washed with a small amount of methanol, and then dried.

Table 1 shows the properties of the obtained copolymer (polymer type ultraviolet absorber).

Example 2: Synthesis of copolymer of 2-hydroxy-4-(2-methacryloxy)ethoxybenzophenone and ethyl methacrylate 167 g of 2-hydroxy-4-(2-methacryloxy)ethoxybenzophenone, 450 g of ethyl methacrylate
g%A I B Nl, 6g, lauryl mercaptan 0
．． A copolymer was obtained as a pale yellow powder by carrying out the same operation as in Example 1 using 615 g of ethyl acetate.

Table 1 shows the properties of the obtained copolymer (polymer type ultraviolet absorber).

Example 3: 2-hydroxy-4-(3-hydroxy-2
- Synthesis of copolymer of 2-hydroxy-4-(3-hydroxy-2-methacryloxy)propoxybenzophenone and methyl vinyl ether 390 g of 2-hydroxy-4-(3-hydroxy-2-methacryloxy) propoxybenzophenone, 180 g of methyl vinyl ether, A I B Nl, 65 g,
Lauryl mercaptan 0.7g.

Using 570 g of ethyl acetate, the same operation as in Example 1 was performed to obtain a copolymer as a pale yellow powder.

Table 1 shows the properties of the obtained copolymer (polymer type ultraviolet absorber).

Example 4: Synthesis of copolymer of 2-hydroxy-4-methacryloxybenzophenone and butyl acrylate 150 g of 2-hydroxy-4-methacryloxybenzophenone, 280 g of butyl acrylate, A I B N
The same operation as in Example 1 was performed using 1.8 g of lauryl mercaptan, 0.7 g of lauryl mercaptan, and 400 g of ethyl acetate to obtain a copolymer as a pale yellow powder.

Table 1 shows the properties of the obtained copolymer (polymer type ultraviolet absorber).

Example 5: Synthesis of copolymer of 2-hydroxy-4-(2-acryloxy)ethoxybenzophenone and vinyl acetate 120 g of 2-hydroxy-4-(2-acryloxy)ethoxybenzophenone, 280 g of vinyl acetate, A
I B N2.0g, lauryl mercaptan 0.9g,
Using 400 g of ethyl chloride, the same operation as in Example 1 was carried out to obtain a copolymer as a pale yellow powder.

Table 1 shows the properties of the obtained copolymer (polymer type ultraviolet absorber).

Test Example 1 Acrylonitrile 70% by weight, vinyl acetate 10% by weight,
After dissolving an acrylic polymer copolymerized with 20% by weight of vinylidene chloride in DMAc, the copolymers (polymer type UV absorbers) obtained in Examples 1 to 4 were added to the acrylic polymer as shown in Table 2 below. It was added in the indicated amount to prepare a spinning dope for fiber production. The spinning stock solution obtained in this way was
After extrusion into a coagulation liquid using a spinneret with a diameter of 1 mm and 100 holes to coagulate the product, the sample was washed with water and dried.

The obtained acrylic fiber was subjected to an exposure test using a fade meter (Model FA-2, manufactured by Toyo Rika Kogyo Co., Ltd.).
The degree of yellowing of the acrylic fibers was examined using a colorimeter (Model Z-1001DP, manufactured by Nippon Denshoku Industries Co., Ltd.). The measurement results are shown in Table-2.

Comparative Example 1 Acrylonitrile 70% by weight, vinyl acetate 10% by weight,
After dissolving an acrylic polymer copolymerized with 20% by weight of vinylidene chloride in DMAc, 3% by weight of 4-octoxy-2-hydroxybenzophenone was added to the acrylic polymer to prepare a spinning dope for fiber production. Using the spinning dope thus obtained, acrylic fibers were obtained in the same manner as in Test Example 1. The obtained acrylic fibers were subjected to the same test as in Test Example 1, and the results are shown in Table 2.

Test Example 2 After dyeing each acrylic fiber obtained in Test Example 1 and Comparative Example 1 under the following conditions, the light resistance of the dyed product was determined according to JIS L 0.
Table 3 shows the results of testing according to 842 (Test method for dyeing fastness to carbon arc light).

Dyeing conditions Dye C, 4Ba5ic YellowLL+40 0.
3% (owf) acetic acid 2,0% (owf)
f) Sodium acetate, 0.5% (otf) Catibon L K 1.0% (oibf) (level dyeing agent manufactured by Nichisha Yushi Kogyo ■) Bath ratio 1:20 Dyeing temperature/time 100°C x 30 minutes Table - 1: Properties of copolymers obtained in Examples 1 to 4 *I)
GPC analysis (standard polystyrene equivalent) *2) Ultraviolet transmittance of the copolymer at wavelengths of 290 nm and 330 nm in a 5μ/]00 mfl chloroform solution by ultraviolet spectroscopic analysis (blank below) Table 3 = Results of Test Example 2 Patent applicant: Ichisha Yushi Kogyo Co., Ltd.

Claims (1)

[Scope of Claims] 1. A copolymer of a benzophenone compound represented by the following general formula (I) and a vinyl compound copolymerizable with the compound, wherein the benzophenone compound is
An ultraviolet absorber for acrylic fibers, characterized by comprising a copolymer containing % by weight. ▲There are mathematical formulas, chemical formulas, tables, etc.▼…(I) (In the formula, R: hydrogen or methyl group
Chemical formulas, tables, etc. are available ▼) 2. The vinyl compound has an alkyl group with 1 to 4 carbon atoms.
Acrylic acid alkyl ester or methacrylic acid alkyl ester of
The ultraviolet absorber for acrylic fibers according to claim 1, which is an alkyl vinyl ester of No. 4. 3. The weight average molecular weight of the copolymer is 5000 to 100
3. The ultraviolet absorber for acrylic fibers according to claim 1 or 2, wherein the UV absorbent is 000. 4. A copolymer of a benzophenone compound represented by the following general formula (I) and a vinyl compound copolymerizable with the compound, wherein the benzophenone compound is
1. A method for photostabilizing acrylic fibers, which comprises incorporating a copolymer containing % by weight in a spinning dope containing an acrylic polymer, and wet-spinning this spinning dope to obtain acrylic fibers. ▲There are mathematical formulas, chemical formulas, tables, etc.▼…(I) (In the formula, R: hydrogen or methyl group
5. The method for photostabilizing acrylic fibers according to claim 4, wherein the acrylic polymer forming the acrylic fiber is an acrylic copolymer containing a halogen monomer as a copolymerization component. . 6. The vinyl compound is an acrylic acid alkyl ester or methacrylic acid alkyl ester in which the alkyl group has 1 to 4 carbon atoms, or an alkyl group in which the carbon number is 1 to 4.
Claim 4 is an alkyl vinyl ether or an alkyl vinyl ester in which the carboxylic acid residue has 1 to 4 carbon atoms.
or 5. The method for photostabilizing acrylic fibers according to 5. 7. The weight average molecular weight of the copolymer is 5000 to 100.
000. The method for photostabilizing acrylic fibers according to any one of claims 4 to 6.